Screen-rim.



P. H. BAAGK.

SCREEN RIM.

APPLIUATION FILED 11017.22, 1910.

Palzented Apr. 4, 1911.

WITNESSES:

FTQ.

PETER H. BAAGK, OF SAN FRANCISCO, CALIFORNIA.

SCREEN-RIM.

Specification of Letters Patent.

Patented Apr. a, 1911.

Application filed November 22, 1910. 7 Serial No. 593,635.

To all whom it may concern:

Be it known that 1, PETER HENRY BAAGK, a citizen of the United States, residing at San Francisco, in the county of San Francisco and State of California, have invented new and useful Improvements in Screen- Rims, of which the following is a specification.

The present invention relates to an improved screen rim.

It is a matter of common experience that all screens wear out much sooner in the screening or perforated portion thereof than in the rim or unperforated portion. This being the case it is obviously of great utility to provide a screen having a perforated or screening portion detachably connected to the rim or unperforated portion, so that the former can be replaced by other screening material when worn out. This detachability is also very desirable on account of the advantage thereby obtained of being able to use screening material of any desired mesh with the same rim, thereby greatly saving in expense. Notwithstanding the great utility of such construction, no device of this kind is extensively, if at all, on the market. The reason undoubtedly is the difiiculty of providing a connection between the screening material and the rim portion which will permit them to be detached from one another and will yet hold them together very securely when in use. In my improvement I provide a means for overcoming this difilculty.

In the accompanying drawing, Figure 1 is a transverse section of a screen constructed in accordance with my invention; Fig. 2 is a broken plan view thereof; Fig. 3 is an enlarged detail section showing more particularly the groove and teeth.

Referring to the drawing, 1 indicates an outer rim section and 2 an inner rim section, fitting closely within the outer section. Said sections are here shown as round, but they may be made square or oblong or of any desired form. Said sections are slightly conical at their upper or larger ends, and are formed with flanges 3, 4, having co-registering holes 5 through which are passed bolts 6 on which are screwed nuts 7 to hold said flanges together.

8 indicates screening material, here shown as of wire cloth, although it may be made of cheese cloth or any other desired sheet ma terial having perforations.

The outer rim 1 is formed at its lower or smaller end with an inwardly and upwardly extending flange 10 forming a groove 11, and over the edge of said flange and on said grooved portion is laid the marginal portion of the screen 8. The lower or smaller end of the inner rim is formed with teeth 13. l/Vhen the rims are secured together by means of the bolts said teeth 13 press the marginal portion of the screen 8 into said groove 11 and secure it therein.

I find that by the above construction the screen is very firmly secured to the rim,whereas all other constructions, of a simple character, which permit the screen to be detached from the rim, do not hold it with sutlicient security when attached. Even if the lower edge of the inner rim presses the margin of the screen into the groove it will not hold it with absolute security against greatstrain upon the screen unless it be serrated as shown, although it may hold it sufficiently well when there is not such strain thereon, and therefore I regard it as within the scope of my invention, although an inferior form thereof.

By this construction I greatly economize in the cost of using screens; first, because when the screen proper is worn out it may be replaced by a new one at trifling expense without having to renew the rim; second, because screens of a large number of different meshes may be kept on hand without requiring a rim for each screen; third, the expense of transportation and storage of screens is greatly reduced.

I claim The combination of an outer rim, formed at its lower end with an inwardly and upwardly ext-ending flange forming a groove, a screen, a marginal portion of which is laid over the edge of said flange and on said grooved port-ion of said outer rim, an inner rim, the lower end of which is formed with teeth received between said flame and the In testnnon whereof I have hereunto set I n J I 23 u k c mzun portion of 116 outer run, and enmy hand 1n the presence of two subserlbl0 gaging the inerglnal portlon of the screen, lng Witnesses.

z 1* '0- 1; 7 emu]. 1 nier end o rter lime beln o neot at PETER H BAAOIL their upper ends with outwardly extencung flanges and bolts for vressni sand latter V1 1tnesse2 g) 7 C3 flanges closely together, substantially as de- Fmmors M. \Vlzrorrr, scribed. D. B. RICHARDS.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

